The man, a pyrotechnist, was being questioned by police late Thursday, said Lt. Willie Guerrero of the Van Nuys Division of the Los Angeles Police Department. Guerrero said he did not know whether the man is a licensed pyrotechnist.

Officers went to the address listed on the package and found a large quantity of explosive materials at the home in the 7900 block of Genesta Avenue, Guerrero said.

"We have a situation where a resident had explosives stored in the home and we evacuated the neighborhood," Guerrero said. "We are trying to ensure the safety of the residents and emergency personnel."